The sea saw, and fled He does not enumerate in succession all the miracles which were wrought at that time, but briefly alludes to the sea, which, though a lifeless and senseless element, is yet struck with terror at the power of God. Jordan did the same, and the very mountains shook. It is in a poetical strain that the Psalmist describes the receding of the sea and of the Jordan. The description, however, does not exceed the facts of the case. The sea, in rendering such obedience to its Creator, sanctified his name; and Jordan, by its submission, put honor upon his power; and the mountains, by their quaking, proclaimed how they were overawed at the presence of his dreadful majesty. By these examples it is not meant to celebrate God's power more than the fatherly care and desire which he manifests for the preservation of the Church; and, accordingly, Israel is very properly distinguished from the sea, the Jordan, and the mountains -- there being a very marked difference between the chosen people and the insensate elements.

The sea saw it - The word it is supplied, not very properly, by our translators. It would be more expressive to say, "The sea saw:" that is, The sea - (the Red Sea) - saw the mighty movement - the marshalled hosts - the moving masses - the cattle - the pursuing enemies - the commotion - the agitation - on its usually quiet shores. We are to conceive of the usual calmness of the desert - the waste and lonely solitudes on the banks of the Red Sea - and then all this suddenly broken in upon by vast hosts of men, women, children, and cattle, fleeing in consternation, followed by the embattled strength of Egypt - all rolling on tumultuously to the shore. No wonder that the sea is represented as astonished at this unusual spectacle, and as fleeing in dismay.
And fled - As if affrighted at the approach of such an host, coming so suddenly upon its shores.
Jordan was driven back - Referring to the dividing of the waters of the Jordan when the children of Israel passed over to the promised land. Joshua 3:13-17. They also seemed astonished at the approach of the Hebrews, and retired to make a way for them to pass over.

The sea saw it, and fled - Mr. Addison has properly observed (see Spect. No. 461) that the author of this Psalm designedly works for effect, in pointing out the miraculous driving back the Red Sea and the river Jordan, and the commotion of the hills and mountains, without mentioning any agent. At last, when the reader sees the sea rapidly retiring from the shore, Jordan retreating to its source, and the mountains and hills running away like a flock of affrighted sheep, that the passage of the Israelites might be every where uninterrupted; then the cause of all is suddenly introduced, and the presence of God in his grandeur solves every difficulty.

The sea saw it, and fled,.... When the Word of the Lord appeared at it, as the Targum in the king's Bible; the Red sea, to which the Israelites came when they went out of Egypt; this saw that Judah was the Lord's holy and peculiar people, and that Israel were the subjects of his kingdom; it saw the presence of the Lord among them; it saw him in the glory of his perfections, and felt his power; see Psalm 77:16, at which its waters fled and parted, and stood up as a wall to make way for Israel to pass through as on dry land, Exodus 14:21. This was typical of the nations of the Gentile world, comparable to the sea, Daniel 7:2, who saw the work of God going on among them under the ministry of the Gospel in the first times of it, whereby multitudes were turned from idols to serve the living God; this they saw and trembled at, and they and their kings fled for fear; see Isaiah 41:5, and of the stop put to the ocean of sin in a man's heart, and to the torrent of wickedness that breaks out from thence, by powerful and efficacious grace, much more abounding where sin has abounded.
Jordan was driven back; this was done not at the time of the departure of the Israelites from Egypt, but just before their entrance into the land of Canaan, and in order to it; and being an event similar to the former is here mentioned, and done by the power and presence of God; for as soon as the feet of the priests who bore the ark of the Lord, the symbol of the divine Presence, were dipped in the brim of the waters, the waters below were cut off from those above, and stood up on an heap, and all the Israelites passed through on dry ground, Joshua 3:13, this was an emblem of death, through which the saints pass to glory, which is abolished by Christ, its sting and curse taken away; which when the saints come to, they find it like Jordan driven back, and have an easy and abundant passage through it; and when on the brink of it, and even in the midst of it, sing, "O death, where is thy sting? O grave, where is thy victory?" 1-Corinthians 15:55.